Pothovoltaic panel power output booster and method

ABSTRACT

A booster for PHOTOVOLTAIC (PV) panel(s) output power utilizes the low output voltage generated by the PV panel(s) during none optimum operating conditions, to enhance the power output level of PV panel(s). It should be noted for sake of brevity the phrase “PV” is used for photovoltaic. The booster module described, operates only on energy provided by the PV panel(s) that is connected to, and does not require any other source of energy. Booster operation is implemented such that, when it is disabled, during normal PV panel(s) output levels (typically 50% to 100% of the PV panel rating), it does not adversely affect the PV panel efficiency. The booster module is comprised of electronic circuitry that monitors the output of PV panel(s). Multiplies PV panel(s) low level DC output voltage, using charge pump capacitive voltage multiplier circuits, and stores this energy in a capacitor bank. The stored energy provides the power supply function for the controller, high frequency bias generator, and the other booster circuitry. The high frequency bias generator pulses are reinjected into the PV panel output to enhance the PV panel output power while the booster is active.

BRIEF DESCRIPTION OF THE DRAWINGS AND EXPERIMENTAL DATA

FIG. 1 is a block diagram of a typical environment of a power boosterfor a photovoltaic panel according to exemplary embodiments of thepresent invention;

FIG. 2 is a block diagram of a power booster for according to exemplaryembodiments of the present invention;

FIG. 3 is a flowchart of a method for boosting the power output of thephotovoltaic panel according to exemplary embodiments of the presentinvention; and

FIG. 4 is a diagram illustrating the power output enhancement of thephotovoltaic panel according to exemplary embodiments of the presentinvention.

TABLE I is a sample of collected data of a charge pump capacitivevoltage doubler driven by a photovoltaic panel according to exemplaryembodiments of the present invention;

TABLE II is a sample of collected data showing the effect of injectedhigh frequency booster bias pulses into the photovoltaic panel outputterminal according to exemplary embodiments of the present invention;

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description is of the best currently contemplatedmodes of carrying out exemplary embodiments of the invention. Thedescription is not to be taken in a limiting sense, but is made merelyfor the purpose of illustrating the general principles of the invention,since the scope of the invention is best defined by the appended claims.Broadly, an embodiment of the present invention generally provides apower booster device and a method for boosting the power output of aphotovoltaic panel, during the morning and afternoon hours, when in thenormal operating mode the photovoltaic panel output is not consideredadequate.

FIG. 1 shows a simplified block diagram of a typical environment of apower booster for a photovoltaic panel 12. The environment of a powerbooster 10 may include one or more PV panels 12. The PV panels 12 may becoupled to the power booster device 20. The power booster device 20 isused for controlling and interacting with the PV panel 12. Theenvironment of a power booster 10 may also include a load 14. Load 14may be coupled to PV panel 12 via booster 20.

FIG. 2 shows a block diagram of the of power booster device 20. Powerbooster device 20 is for determining if the PV panel 12 is receivingenough energy from the Sun for generating electrical energy to the load14 and when needed try to boost the output power PV panel 12. For thisoperation, the power booster device 20 does not require auxiliary powersource. Booster generates its own power requirements by using the PVpanel 12 provided low output voltage and processing it through a chainof series/parallel connected charge-pump capacitive voltage doublerdevices. The output stage of the voltage multiplier circuits stores thebuilt up energy in a low Equivalent Series Resistance (ESR) capacitorbank at a controlled level and supplies the boosters' other circuitswith the required input power. Table I displays test data collected froma low level voltage doubler driven by a PV panel 12.

Power booster device 20 includes a DC voltage multiplier 23. The DCvoltage multiplier 23 receives input power from the PV panel 12 viainput terminal 27. The DC voltage multiplier 23 is coupled to aController 22 and to a High Frequency bias generator 24. The Controller22 monitors the DC voltage provided by the PV panel 12. The controller22 determines if there is enough voltage to boosting operation or thereis enough energy for regular operation (without boost) of PV panel 12.Controller 22 is coupled to a high frequency (HF) bias generator 24. TheHF bias generator 24 is turned-on when power boost is needed. Output ofthe HF bias generator 24 is coupled to input terminal 27, via an ACcoupler 25, to inject a high frequency bias to the PV panel 12 via inputterminal 27. High frequency pulses may induce bias in crystal structureof the semiconductor layers of the PV panel 12. The induced bias mayincrease the electron mobility in the semiconductor layer of PV panel12. Table II shows the effect of booster signal injected into the PVpanel 12 via input terminal 27 at several operating levels. The DCoutput of the PV panel 12 may be outputted to the load 14 through an HFfilter 26.

The power booster device 20 is implemented such that it does notsignificantly degrade the efficiency of the PV panel 12 when the booster20 is inactive.

FIG. 3 shows a flowchart, illustrating a method 30 for boosting thepower output of the PV panel 12. Method 20 may start at step S31. Instep S32 it is determined if there is enough power to boost, if not theprocess loops back to step S32, otherwise in step S33 boost is started.In step S34 it is determined if there is enough power from the PV panel12, if not the process loops back to step S33 to continue boosting,otherwise in step S35 AC generation is started. In step S36 it isdetermined if there is enough power from the PV panel 12 without boost,if not the process loops back to step S33, otherwise in step S37 theboost is stopped.

FIG. 4 is a graph illustrating an exemplary power output gain of thephotovoltaic panel by employing a power booster device. Bell shape curve41 represents the possible output voltage of an un-boosted PV panel;Bell shape curve 44 represents a typical output voltage of a boosted PVpanel. Line 42 shows a voltage level above which no boost is needed.Line 43 shows a voltage level above which boost may provide power outputgain.

It should be understood, of course, that the foregoing relates toexemplary embodiments of the invention and that modifications may bemade, for higher power PV panels, without departing from the spirit andscope of the invention as set forth in the following claims.

We claim:
 1. A method for boosting the power output of PV panel,comprising of: a) monitoring PV panel output power, b) determining ifthere is enough power from the PV panel for boosting, c) startingboosting, d) determining if there is enough power from the PV panel forenergy production, e) starting boost for power generation, f)determining if there is enough power from the panel without boosting;and g) stopping boosting. 2: A power booster device for boosting thepower output of a PV panel; comprising of: a) a DC voltage multipliercoupled to an input terminal, b) a high frequency bias generatorreceiving power from the DC voltage multiplier, c) a controllerreceiving power from the DC voltage multiplier and controls the highfrequency bias generator, d) an AC bias coupler connected to the inputterminal, e) a high frequency filter connected between the input andoutput terminals.